Railway-traffic-controlling apparatus



Noy. 4, 1930. G. w. BAUGHMAN 1,780,737

'RAILWAY TRAFFIC CONTROLLING APPARATUS Filed Oct. 29, 1929 INVENTOR 2 Patented Nov. 4, 1930 unrrno 5 m PATENT OFFICE, f

GEORGE w. BAUGHMAN, or PITTSBURGH,PENNSYLVANIA, ASSIGNOB, T0 THEUNION swrrcn & SIGNAL COMPANY, or SWISSVALE, PENNSYLVANIA, A CO PORATION OF PENNSYLVANIA RAILWAY TRAFFIC-CONT'ROLLING APPARA'LU'S Application filed October 29, 1929. Serial llo. 403,198.

My invention relates to railway trafliccontrolling apparatus, and particularly to apparatus of the type wherein apparatus carried on a railway Vehicle co-operates with track-v way apparatus for controlling the vehicle.

I will describe two forms of railway traffic controlling apparatus embodying my inven tion, and will then point out the novel features thereof in claims.

In the accompanying drawing, Fig. 1 is a diagrammatic view showing one form of railway traffic controlling apparatus em bodying my invention. Fig. 2 is a diagrammatic View showing a modification of the ap paratus of Fig. 1, and also embodying 'myinvention. 1

Similar reference characters designate similar parts in each of the two views Referring first to Fig. 1, the reference characters 1 and 1 designate the'track' rails of a stretch Y of railway track on which a railway vehicle, designated by the reference character V, is moving toward theend A of a section of track which is separated from adjoining portions of stretch Y by means of insulated joints 2. A track transformer T, which is connected across the rails adjacent the exit end A, supplies this section with alternating current. Transformer T is, in turn, supplied with current over wires or and 0 from a source not shown in the drawing.

Mounted on vehicle V are two laminated iron cores h located over the track rails, respectively, each core being U-shaped and with its legs pointing downwardly, and each core being disposed transversely with respect to the rail. It is apparent, therefore, that when alternating current flows in either rail, part of the magnetic lines of force surrounding such rail will pass through the core which is directly over the rail, and so will induce an alternating potential in any coil which the core may carry. The core h over rail 1 is wound with a coil a and the core h over rail 1- is wound with a coil a Coils a and a are included in a circuit passing from coil a through primary winding 3 of transformer F primary winding 3' of transformer F and winding a back to winding (1 A second circuit passes from coil through winding3 of transformer F a tuning condenser 5, and primary wind ing 8 of a transformer G back to winding a A third circuit passes from coil aflthrough primary winding 3 of transformer F condenser.5, and winding 8 of transformer G backto coil (11?. Coil a and the other parts of the third circuitare proportioned'exactly the same as thecorresponding parts of the second circuit. A fourth circuit passes'from secondary winding 4 of transformer 'F through a condenser 6, and-the secondary winding l of transformer F back to winding 4 of transformer F 1 Coils a and a are sowound on their .cores k that, at a given instantrwhen a potential created in windinga by current flowing in a given direction in rail 1 is positive-at terminal 24'of' winding a a potential created I in winding a by current flowing in rail 1'- in the direction opposite to that ofthe' flow of current in rail 1 will be positive at terminal 25 of winding a It is evident, therefore, that when current flows in oppositedirections in rails 1 and 1, the potentials created in windings a and a 'opposeeach other. When the potentials thus created in coils a and a are exactly equal to each "other, the current flowing from coil a willflow through the second circuit only, and the current at the same time flowing from coil a will follow the third circuit only.

Hence all the current coils a and a ,.under these conditions, passes through winding 8 of transformer G, causing alternating current to flow in a circuit which includes a condenser 7 and secondary wind ing 9 of transformer Cr. The current'fiowing this circuit creates an alternating difference of potential between grid 11 and filament 12 of an electron tube K. Filament 12'is constantly heated byv a battery 13. Tube K may be used to control the vehicle V on which this tube is carried. Anexample of such control a and a are equal and opposite to each other,

flowing from both the currents flowing in the second and third y will now assume that duetoa broken circuits are also equal to each other and create-potentials in windings 4 of transformersF and F 2 which are equal and opposite to each other, and henceno current flows through theufourth; circuit which includes windings 4:.

rai'lf no current is fi'owin'g in rail 1; buttha-t the current'flowing'in rail-I returnsto-transformer T by some other path S11Cl1,f01 example, as a rail of an adjacent track which is cross-bonded to rail "The p'Ote'ntiaI'iir .duced .in coil a? will,,unc lerthisv condition,

send current through the first and second circuits: The current n'ow passing through winding 3 oftransformer F induces a pc- I tential-in winding 4' oftransformer F which vsends current through: winding: of transformer.l ;1 The curre-nt tlrus supplied to winding 45 of'trans-former- F inrducesiin windingiifi of transformer F potential which helpsthe potential ofcoilt a? to send current through" the first; circuit. 0n account of'the potential thus induced in: wind:

ing 3 of transformer Fitlicurrent: passing through wrnd1n1g8fiof: trans-forineraG will be reduc'e'd an'd ther more nearly the potential induced in winding'8oftransformen-F equals the potential of coil a ther'lesswill be the currents flowingthrough windingtS- oftra -isformenG;

I If the current flowingft lrrou gh oneofithe rails of stretch. Y isof lo-wern ragnitude:than I that flowing throughthe other railyifor eX- ample if the current flowing insr-ail I1 is less I flowing through WindingSoftrans-former G,

than thatflowing inrail lithe largerfcurrent thus induced in coil a will cause a: potential to beIind -uced inr winding 3 oftransformer F in opposition to thepotential .of coil a ,an-d*will: thus h'eipreduce the current From theforegoing',.it.i isev-ident that if the potentialcreated in either ofthe' coils alis' less than that in the other coilgzthecur rent flowing through windirigmS-of trans former G will. be reduced bythe action: of

transformersF- and F Referring now toiFig. 2, vehiclervishere showncarryingtwo GOI'lS a axand a wound on cores h, and transformer T supplies current to stretch Y adjacent point zAe "exactly asLin Fig, 1 In Fig; 2', however, eachof the coils a'is' included in. only one circuit, re-

of-an electron tube L Filament 18 of tube 1 transformer F L is constantlyenergiz ed by a battery 19.

'Because of the alternating difference of potential between grid 17 and filament 18, al-

ternating current is superimposed on the direct current which is supplied. by battery 20 to the. plate circuit for electron tube: L This plate circuit passes from battery 20, through the primary winding 21 of a transformerI-I,

and plate to filamentoftube L bacl'rto-bat tery 20-; Transformeris providtadwith two primary windings,2T a=nd-22feach of whichisconnectedto a terminal 28. WVhen 'wi'ndiiig121"isenergized; as just described, -a'n.alternat ngpotent al 1S nduced in secon dary winding 23 of' transformer H, which causes curreniatoiv flow 1n:v a-c1rcu1t:.1=ncluchng a condenser '17. Air alternating-difference of I potential-isthereby created: between; gridi 11 andrfilainent 12: of an electronitube'lfi which,

similarly' totv tube Kin: Fig: lycontuol s tlre vehicle-V onawlrich'tuhe'K is; carried.

@oil supplies current'to. circuit which is similar.to theoireuit alreadydescribedfor coil a and which includes primarywinding 3 of a transformer E 1 condenser-1.4,. and

primary winding 15: ofa transformer M Transformer" M by means of? acircuit. including al'condenser 'ZP-and; secondary: Winthing 1 63, icreates-t an?" alternating; dit'l erence :of

potential between grid; L? and filament; 18 of an electron tube L 'Alternatingcuiment is.-therefor'e'superimposedon the direct cur rent which-is supplied by battery QOqtotlie platef circuit for tubezL l. This plate. circuit passesfrom battery 2.0, v throughwinding 22 of transformer: and plate 'toifil'ament of. V

electron" tube h back to battery 20:;

The circuits are so arranged thatatthe instant thepolarity of? grid. 17. of tube", L? is positive the potential'iofgrid 17 oftnbe L is:negative when; the current flows. inioppo site directions in. rails land-l I Eherefore the? magnetic flux produced] by one offlthe win-dings 2L and: 22 ofv transformeroreases'wlrile: the fluxproducediby the other of these windings increases. and: hence-the potentials created winding-28.- by: these 'fluxesare'add'ed together; 1 If the current supplied-by coil or to trans:- formerF is of the-same inagnitude'astl'io current supplied by coil a toe transformer F no current. will flow 'in. the circuit of secondary windings 4 of these trans-formers,

since the potentials created in thesewind' will then beequa'l and opposite-.. If, however, the potential created in coil a isless than that created in coilafi then the potential created in winding 4a of trans former F willbegreater'than that created in winding 4 of transformer "F and hence the potential of winding'toftransformer-F will cause a current to: flow in opposition tothe potential created in secondary winding 4 of current being suppliedv to winding: 15 0f This. results in a. smaller llO transformer M and hence the current supplied to the plate circuit of tube L will also be reduced, resulting in a lower energization of transformer H. In this way, current of lower magnitude will be induced in the circuit comprising condenser 7 and winding 23 of transformer H. As a result, a lower potential difference will be produced between grid 11 and filament 12 of tube K, resulting in an alternating plate circuit current of lower magnitude for tube K. If the potential induced in coil a were still less, the alternating current which could flow in the plate circuit for tube K would clearly be still less.

If current should flow in the same direction and of the same magnitude in rails 1 and 1 the current supplied to winding 15 of transformer M would be of the same magnitude and the same polarity as the current supplied to winding 15 of transformer 1 and hence the grids 17 of tubes L and L respectively, would be of like polarity at all times, and hence the current supplied to the plate circuits for tubes L and L would be of equal magnitudes, and would be flowing at the same time in opposite directions through the windings 21 and 2:2 of transformer I-I. thus balancing each other, with the result that no current would flow in the circuit including secondary 23 of transformer H, and therefore there would be no difference-of potential between grid 11 and filament 12 of tube K, and hence no alternating current could flow in the plate circuit for tube K.

From the foregoing description and the accompanying drawing, it will be understood that apparatus comprising my invention protects against false operation of train carried governing means by current flowing in one rail only or of lower magnitude in one rail than in the other rail, as in the event of a broken rail which is bonded to an adjacent rail of another track, or by current flowing in the same direction in the two rails, as in the event of a surge of the propulsion current on a railway on which the trains are electrically operated. Surges of propulsion current usually divide and flow in the two rails and in the same direction.

Although I have herein shown and described only two forms of railway tralfic controlling apparatus embodying my invention, it is understood that various changes and modifications may be made therein within the scope of the appended claims without departing from the spirit and scope of my invention.

Having thus described my invention, what I claim is':

1. In combination, a stretch of railway track, means for so supplying said stretch with periodically varying current that ata given instant said current flows in one direction along one rail of the track and in the opposite direction along the opposite rail of the track, a device in which current is induced bycurrent flowing alongzsaid first rail, a second device in which current is induced by current flowing along said opposite rail, av

first transformer, a second transformer, a circuit including the primary windings of said transformers and said first and second devices so connected in series that current induced in said first device by current flowing in one direction in said first rail opposes current induced in said second device by current flowing in the opposite direction in said opposite rail, a railway traflic control meansso connected with said circuit as to "complete a second circuit including said first device and the primary winding of said first transformer and to complete .a third circuit including said second device and the primary winding of said second transformer, and a fourth circuit including the secondary windings of said transformers. I

traclg'means for supplying said stretch withcurrent flowing in one direction along onerail at a given instant and with current flowing'in the opposlte direction along the opposite rail at the same instant, a device inwhich current is lnduced by current flowing alongsald first rail, a second device .in which current is induced by current flowing along said opposite rail, a first transformer, a second transform- .the primary winding of said first transformtransformer, a third circuit includingthe secondarywlnd ngs of sald transformers, and

said first and second circuits.

3. In combination, a stretch of railway track, means for supplying said stretch with current flowing in one direction in one rail" at a given instant with current flowing-in the opposite direction in the opposite rail at the same instant, a device in which current .is induced by current in said first rail, a second device in which current is induced by current in said opposite rail, railway traffic control means supplied withcurrent said first and second de ices. and means operating when the current induced in one of said devices is reduced below the current induced in the other said device to reduce the current supplied to said control means by an amount more than that due to the reduction of the current supplied to said one device. I

4. In combination, a stretch of railway track, means for supplying both rails of said stretch with current, a railway traffic control device in which current is induced by the current flowing in each of said rails, and means operating when the current in one of said rails is reduced below the current in the In combination, a stretch. of .railway.

er, a circuit including said. first device and railway traffic control means controlled by w '4 p Y 780,737

thellrediuction or the. current. in said one rail. f5. -'In}coi-"nbi11ation,' a stretch of railway traek' me-ans: for supplying both rails'of said stretch with current a railway traflicwcontrol device, means for supplying said device with current which is controlled by the current flowing-in each oif'said rails, and means operating when the current flowing one of said I rail sis reduced below the current flowing in w the other'saidr rail to; reduce the current in said device: by an amount greater than that dinette the'reduction oit' the current in said one rails.) q a '-(f3*.;-]in;"con-rbination, a 7 stretch of railway 15 track means fOrsup-plyingboth rails or said 'stretch' with current; vehicle control means carriedon a vehicle and controlled by the current-flowing in; each of said rails, and auxiliaryjmeansconitrolled bythe: current fiow v 29 .ing eac-hiof said rails and operating p when the current flowing in one of said rails V is reduced below the current flowing in the 1 other said rail to reduce the current supplied V to. said control means by an amount greater i han tha-t due-to the reduction of the currentsaidone ra-il .c 7x111; combination, a stretch of railway 7 track, means'for supplying bothrails of-said stretch with current; vehicle, control means 30 carriedxonavehicle and controlled by the current flowing in'each of said rails, and two transformerscontrolled bythecurrentflowing flowing in one: of said rails is reduced below I 5 the current flowing in the. other said rail to reduce the current. supplied, to said control 1 meansby amount greater than thatdueto *the. reduction eithe current in said one rail. 7 8. In combination, a stretch of railway go track,v meansfor supplying both rails of said stretch with current, a: railway trafiic control 'lde icecontroliled by current inboth said rails, andmeansoperating when the current in one 7 of said rail-sis of lower magnitude than the current in the other 'ofsaid railsto reducethe currentsuppliedto said'control means'hy an amount greater than that, due. to the-lower magnitude of: the current in the said one rail. =fn-testirnonyz whereofI aflix'my signature.

m 7 cnoaenw, BAUGHMAN- in said railsand operating when the current 

